They used 2 different machine streets for the producing of 7.9 Mauser rounds.
For error identification they marked the head stamp. It was known that the “fb” head stamps exist with and without a dot behind the factory code.
The way they made the head stamp of the material code was not noticed by me as identification of the production line.
Still learning…

Dutch - Excellent information! Thanks. I never noticed the difference on the material codes, but always thought the dot might be for different production lines, but never had any corroboration. Thanks!

I have noticed the difference in the letters in the materiel codes but didn’t know the reason behind it. Now, I will have to dig out my duplicates and see if I have overlooked some. Thanks for the information!

I got to wondering; if the style of the letters in the materiel code identified which production line steel cases were made on, what about brass cases? The only major difference I can find is the style of “P” used in P334. There are two different types. One has a straight top, the other a curved top. There are also two different style stars. Whether or not that means anything is another story.